Class 16 Emotions (10/19/17) Chapter 10 Notes By: Rashea Psych 302 10/19/17 Emotions The issues o Innate or learned? o Voluntary or involuntary? (conscious/unconscious) o Adaptive behavior or communication? o Emotional expression vs emotional experience o Do animals have emotions? If the emotions are there, the neurons are there as well Measuring emotions o 1) Behavior (emotional display) You can display emotion without having it o 2) Autonomic system (heart rate, breathing, sweating) The polygraph o 3) Endocrine system (hormone levels, E, NE) Stress o Facilitation cascade: one level triggers another Endocrine autonomic behavior The Four Theories Common sense o Perception feeling of fear physiological reaction James Lange View o perception physiological reaction feeling of fear Canon-Bard o Feeling of fear Perception Physiological Modern Biopsychological View o Feeling of fear Perception Physiological reaction feeling of fear etc. (Essentially a Circle) James-Lange Theory James-Lange theory: feelings after physiological reactions o Event that produces emotional reaction Neural bases: Limbic System Limbic system: o A network of structures involves in the experience and expression of emotions limbic cortex fornix
mammillary body (part of hypothalamus) amygdala hippocampus Modern Theory (LeDoux): two pathways two routes to the amygdala o 1) fast ( gut reaction ): stimulus thalamus amygdala response o 2) slow ( cognitive ): thalamus primary sensory cortex association cortex hippocampus amygdala response Auditory Fear Conditioning (Fig. 10.3) scientific study of emotions: Fear conditioning fear can be innate or learned Conditioning: association between a neural cue (tone, aka conditioned stimulus) and a relevant negative stimulus (aka unconditional stimulus, electrical foot shocks). Measure: freezing behavior when hearing the tone Abolished by lesions of the (lateral) amygdala Amygdala involved in the acquisition (learning) of fear Good animal model: many studies have shown that the pathways for auditory fear conditioning are similar in rates and humans Figure 10.3 Extinction of fear: VentroMedial prefrontal cortex Extinction: Repeated presentation of the tone alone, after learning (Fig. 10.4) Extinction is NOT forgetting Emotional learning (in rats) is permanent Ventromedial prefrontal cortext is actively involved in extinction of fear (rats and humans) *Learning not to be afraid 2
Figure 10.4 Emotion: The Amygdala The lateral nucleus of the amygdala o Inputs: cortex (primary and association), thalamus and hippocampus o Outputs: striatum (reinforcement learning) and Prefrontal Cortex (planning, extinction) o Involvement: emotional learning, reward perception. Auditory fear conditioning. Conditioned taste aversion. o Expressions of emotion (Fig.10.1) Behavioral Autonomic Endocrine The central nucleus of the amygdala (CE) o Inputs: internal amygdala o Output: hypothalamus, midbrain (PAG), pons, medulla o Involvement: lesion and stimulation studies show that CE is involved in the expression of negative emotions Brain regions that receive inputs from CE (Fig. 10.2) Central Nucleus of Amygdala Focus specifically on: o Lateral hypothalamus o Ventral tegmental area o Locus coeruleus (NE) o PAG o Facial motor nuclei 3
Figure 10.2 Amygdala and Fear Amygdala and fear: evidence o Animal: stimulation of the hypothalamus (CE output): Fear/attack expression (sham rage) o Human: stimulation of amygdala (during neurosurgery): fear experience o Human damage to amygdala: decrease in startle response and emotional memory. Alzheimer s patients memory for emotional events is impaired and correlated with amygdala damage o Human fmri: amygdala is active during the percept of danger o Fear may or may not yield aggression: different neural systems Aggressive Behaviors The expression of aggressive behaviors is genetically programmed. Species specific (hissing, biting, shouting ) In human, it can be learned. o Dogs expression is different than a snake Two types: o 1) threat behaviors/ defense behaviors towards same species: emotional, social hierarchy 4
o 2) predation towards other species: not emotional The cause of aggressive behavior is partly genetic (sexual/reproductive bases, and partly environmental (learning, past experiences) Neural Control of Aggressive Behavior Serotonin: inhibits aggression and risk taking behaviors Measure levels of 5HT metabolite in CSF (5HIAA) in rhesus monkeys (Fig. 10.5) o High level: still alive; shy o Low level: most likely dead; risk takers Human: Prozac is effective at decreasing aggressive and antisocial behaviors Human: twin studies show a genetic basis (Knock out mice) ***Look up **** Emotion: The Ventral-Frontal Cortex (Fig. 10.6) Aggression: the frontal cortex Anatomy o Ventromedial prefrontal cortex: orbito-frontal cortex + cingulate cortex o Base of the frontal lobes o Inputs: thalamus, temporal cortex, ventral tegmental area, Amygdala o Outputs: hippocampus, hypothalamus, amygdala o Role: control of complex emotions. The last part of the brain to mature (~10-12 years old) Reason why young individuals do things adults wouldn t. Brain isn t fully developed. Phineas Gage (Fig.10.7) Evidence and history o 1800s: Phineas Gage o accidental destruction of the (orbito) prefrontal cortex o cognitively normal (e.g. intact learning, normal intellectual abilities). o Emotional problem: Childish, irresponsible, selfish, inappropriate behaviors. Acting like a teenager change of emotional behavior without changing cognitive abilities Ethics and moral judgement (Fig. 10.8) the Trolley Dilemma: saving lives by sacrifice o Scenario 1: change train track to kill 1-person vs 5 o Scenario 2: push one person over the bridge vs kill 5 on the train track o vmpfc involved in personal moral judgements o possible explanation for some types of criminal behaviors o has to be personal for someone to push the person over the bridge understanding of criminal behavior, psychosocial, etc. o criminals can distance themselves and do scenario 1 5
Figure 10.8 Lobotomies 1935: Becky the Monkey o no aggressive behaviors 1949: Egas Moniz and frontal lobotomies: reduction of anxiety, obsessions, and compulsions o found a way to do it in an outpatient procedure through the eye o about 50,000 100,000 cases worldwide 1960 s: SSRI s and anti-depressants. A pharmacological solution to psychotic behaviors lobotomies are banned in some countries (Russia), still legal but rarely used in Europe and US (now called: Neurosurgery for Mental Disorders) summary: vmpfc: takes high level sensory information, matches them to social standards and plans emotional actions. Lesions social judgements can be done in theory, but not in practice What if we had a quiz? (T/F) the VentroMedial Hypothalamus is involved in maternal behaviors o False sexual behaviors medial preoptic area is for maternal behaviors (T/F) a patient with androgen insensitivity syndrome will look female o True The Ventro Medial Prefrontal cortex is involved in (impersonal, personal, neural) morals judgements. Surgical lesion of the Orbitofrontal cortex called a. o Personal; lobotomy The central nucleus of the amygdala o Is involved in the expression of emotions 6